Solving the Riddle of Sudden Cardiac Death in Hypertrophic Cardiomyopathy: The Added Role of Cardiac Magnetic Resonance

Pathological Alterations in Heart Mitochondria in a Rat Model of Isoprenaline-Induced Myocardial Injury and Their Correction with Water-Soluble Taxifolin

Mitochondrial damage and associated oxidative stress are considered to be major contributory factors in cardiac pathology. One of the most potent naturally occurring antioxidants is taxifolin, especially in its water-soluble form. Herein, the effect of a 14-day course of the peroral application of the water-soluble taxifolin (aqTAX, 15 mg/kg of body weight) on the progression of ultrastructural and functional disorders in mitochondria and the heart's electrical activity in a rat model of myocardial injury induced with isoprenaline (ISO, 150 mg/kg/day for two consecutive days, subcut) was studied. The delayed ISO-induced myocardial damage was accompanied by an increase in the duration of RR and QT intervals, and long-term application of aqTAX partially restored the disturbed intraventricular conduction. It was shown that the injections of ISO lead to profound ultrastructural alterations of myofibrils and mitochondria in cardiomyocytes in the left ventricle myocardium, including the impairment of the ordered arrangement of mitochondria between myofibrils as well as a decrease in the size and the number of these organelles per unit area. In addition, a reduction in the protein level of the subunits of the respiratory chain complexes I-V and the activity of the antioxidant enzymes catalase, glutathione peroxidase, and Mn-SOD in mitochondria was observed. The application of aqTAX caused an increase in the efficiency of oxidation phosphorylation and a partial restoration of the morphometric parameters of mitochondria in the heart tissue of animals with the experimental pathology. These beneficial effects of aqTAX are associated with the inhibition of lipid peroxidation and the normalization of the enzymatic activities of glutathione peroxidase and Mn-SOD in rat cardiac mitochondria, which may reduce the oxidative damage to the organelles. Taken together, these data allow one to consider this compound as a promising cardioprotector in the complex therapy of heart failure.

Multiparametric Mapping via Cardiovascular Magnetic Resonance in the Risk Stratification of Ventricular Arrhythmias and Sudden Cardiac Death

Risk stratification for malignant ventricular arrhythmias and sudden cardiac death is a daunting task for physicians in daily practice. Multiparametric mapping sequences obtained via cardiovascular magnetic resonance imaging can improve the risk stratification for malignant ventricular arrhythmias by unveiling the presence of pathophysiological pro-arrhythmogenic processes. However, their employment in clinical practice is still restricted. The present review explores the current evidence supporting the association between mapping abnormalities and the risk of ventricular arrhythmias in several cardiovascular diseases. The key message is that further clinical studies are needed to test the additional value of mapping techniques beyond conventional cardiovascular magnetic resonance imaging for selecting patients eligible for an implantable cardioverter defibrillator.

The use of cardiac magnetic resonance in hypertrophic cardiomyopathy over the past 10 years [2013-2023]: a CiteSpace-based bibliometric analysis

Background

Hypertrophic cardiomyopathy (HCM) is a common genetic cardiac disorder characterized by the hypertrophy of a segment of the myocardium. Cardiac magnetic resonance (CMR) has been widely used in the assessment of HCM. However, no bibliometric assessment has been conducted on the progress of research in this field. This study thus aimed to examine the current state of research into the application of CMR in HCM and the hotspots and trends that have emerged in this field over the past decade.

Methods

A systematic search was conducted on the Web of Science regarding CMR in the assessment of HCM. The databases were searched from 2013 to June 2023. CiteSpace is an application that can be used to characterize the underlying knowledge of the scientific literature in a given field. We used it to analyze the relationship between publication year and country, institution, journal, author, bibliography, and keywords in the field of CMR for the assessment of HCM.

Results

A total of 1,427 articles were included in the analysis. In the assessment of HCM, the findings from the past decade have consistently demonstrated a progressive rise in the quantity of articles pertaining to CMR. The country with the largest number of publications was the United States [310], and the institution with the greatest number of publications was the University College London [45]. The analysis of keywords revealed the diagnosis and management of HCM with CMR to be the current research focus and emerging trend within this academic field.

Conclusions

This study used a novel approach to visually analyze the use of CMR in HCM assessment. The current research trajectory in CMR consists of the diagnosis and management of patients with HCM. Although most studies confirmed the indispensability of CMR in the assessment of HCM, larger-scale cohorts are still needed to more comprehensively evaluate the role of CMR in the differential diagnosis, pre- and post-treatment assessment, and long-term management of patients with HCM.